Electric alarm for pressure-gages



(No Model.)

'W. H. BRADT. ELECTRIC A-LAEM FOR PRESSURE GAGES. No. 614,697. Patented Feb. 13, 1894 the battery with the gage-case at B and, with the case and index-pinion A forms a I UNITED STATES PATENT OFFICE.

WILLIAM II. BRADT, OF TROY, NEW YORK.

ELECTRIC ALARM FOR PRESSURE-GAGES.

SPECIFICATION forming part of Letters Patent No. 514,697, dated February 13,1894.

1 Application filed November 22,1893.

To all whom it may concern.-

Be it known that I, WILLIAM II. BRADT, a citizen of the United States, residing at Troy, county of Rensselaer, and State of New York, have invented certain new and useful Improvements in Electric Alarms for Pressurewages, of which the following is a specificaiion.

My invention relates to such improvements and consists of the novel constructioh and combination of parts hereinafter-described and subsequently claimed.

Reference may be had to the accompanying tlrawings, and the lcttersof reference marked thereon, which form a part of this specilica-a tion. 1

Similar letters refer to similar parts in the several figures therein.

The object of my invention is to provide an electrical alarm-signal for gages-that can be attached to well known forms of gage with little expense; and to provide for easily and quickly testing the apparatus by causing a contact ot the circuit-closing electrodes by means of mechanism without the case of'the gage.

Figure l of the drawings is a plan view of the face of a common form of pressuregagc provided with my improvementsa portion of the case and dial being broken away to show the testing apparatus. Fig. 2 is a cross-seciion the same taken on the broken line 2 2, in i. Fig. 3 is a view in elevation testing-finger removed.

rring to the drawings, A- represents form of pressure-gage having A- operated by a Eourdon-tube A z in intermediate links in the usual manner, a portion of the tube and one of the links A" being shown in Fig. 1. I

B is an electric battery which nay be of any known form; and 0- is an el ctro-magnetic signal bell located in the battery circuit. A line *ire B- connects one pole of continuous connection between the battery and the index, the index f rming the movlole electrode of the circuit-closing mechanism. The other electrode is formed by the Serial No. 491,612 (No model.)

contaothand D- insulated from the index and having its end offset to form a contactfinger D'in the path of the index. The contact-hand is pivoted concentrically with the index, upon a sleeve D inserted in the central aperture in the dial D surrounding the index-pinion. The sleeve is provided on its lower or inner end with a shoulder D-- abutting on theunder sideof the dial, and its upper or outer end isscrewthrcaded to receive and fit the similarly threaded clampingnut D by means of which the contact-hand is securely clamped to the dial. The dial, with its contact-hand secured thereto, is insulated from the case of the gage and the index in electrical connection therewith, by means of the washers D of rubber'or other insulating material between which the dial is clamped by the screws 3- which secure the dial to the case.

As shown in Fig. 2, the screw S-passes through both washers and the interposed dial, the screw-aperture in the dial being sufficiently large to prevent contact of the screw with the dial.

A binding-post E is secured in an aperture in the case wall by the nut E'- on its inner threaded end, the post and nut being insulated from the case by the, insulating sleeve E and washer E The inner end of the post is connected by the conductorE- with the dial, and the outer end by the linewire B with the remaining pole of the bat tery, whereby the contact-hand D is conneoted through the dial and intervening conductors with such pole of the battery, and forms the'iixed electrode of the circuit-closing mechanism. \Vhen the gage-pressure has caused the index-operating mechanism to more the index into engagementwith the contact-hand, the circuit willbe closed by the contact of the electrodes, and the alarm signal will be rung. By loosening the clamplug-nut D the contact-hand may be oscillated on the sleeve D to assume any radial position on the dial, and may be locked in such position by the clamping-nut. By thus varying the position of the contact-hand, the alarm will be given when the pressure reaches any predetermined degree. By employing two of such contact-hands arranged with their contact-fingers on opposite sides of the index,

I can combine in the same" gage both highe haps, by the electrodes becoming corroded or coated with oil, dust or other matter, which prevents the contact of the electrodes. The latter is frequently the case when the gagepressure reaches its alarm-limit at infrequent intervals.

I have shown in the drawings a device wh ich can be easily applied to an alarm-gage, by means of which the electrodes can be brought into contact at frequent intervals to close the circuit for testing the battery, and remove and prevent any accumulation of dust or other substance upon the electrodes.

A finger F-- is loosely inserted in an aperture in the case-wallot the gage,and secured therein by the shoulder or flange F on the fingerwhich bears upon the outer side of the Wall, and the pin F-'passed through an aperture in the linger on the inner side of the case, as shown in the sectional portion of Fig. 1. The inner end of the finger projects interiorly of the case transversely of the end of the Bourdon-tube; and the outer end of the finger is provided with an operating handle F projecting exteriorly of the case. The finger fitting loosely in the case-Wall aperture, may be oscillated by means of its handle F to act as a lever and force its inner end against the Bourdon-tnbe, moving the tube and other index-operating mechanism of the gage; and producing the same results upon such mechanism and the index as when the tube is subjected to internal pressure. A sufficient movement of the finger will thus cause the index to indicate the alarm degree of pressure and thereby cause a contact of the electrodes, whereupon the alarm will be sounded if the apparatus is in working order. The handle F being accessible from without the gage-case, the testing operation can be repeated very frequently without inconvenience. Besides testing the battery-current, the frequent contact of the electrodes tends since? to prevent accumulations of dust and other substances thereon, keeping their contact surs trical connection with the case; a contact hand pivoted concentrically with theindexin electrical connection with the dial and oitset into the path of the index; a clamp for looking the contact-hand in adjusted positions, and means for connecting the case and dial with the respective polesof an electric battery having an electromagnetic alarm-signal in circuit, substantially as described.

2. The combination with an electric battery having an electromagnetic alarm-signal in circuit,of a pressure-gage having its index electrically connected with one pole of the battery, a sleeve inserted in the central aperture in the dial of the gage, having one end screw-threaded and having a shoulderon the other end abutting on the dial; acontact-hand pivoted upon the sleeve and insulated from the index; a finger on the contact-hand projecting into the path ot the index-;-- an electrical connection between the other pole of the battery and the contact-hand; and a clamping-nut upon the threaded end of the sleeve, substantially as described.

3. The combination with a gage having electrodes arranged to be brought into contact by the movement of the index-operating mechauism, of a lever fulcrumed upon the case wall of the gage, and engageable with the indeX-operat-ing mechanism interiorly of the case, and an operating handle on the lever projecting exterior-1y of the case, substantially as described.

in testimony whereof I have hereunto set my hand this 18th d y of November, 1893.

- WM. H. BRAD-T. Witnesses:

FRANK C. CURTIS, N. DAVENPORT.

EOC 

